The term “worldliness” can have a variety of specific meanings. In context, James talks about “worldliness” in relation to how we treat those around us. Our desires and passions within us can lead us to jealousy and conflict, but God calls us to truly love one another from the heart.
“What causes quarrels and what causes fights among you? Is it not this, that your passions are at war within you? You desire and do not have, so you murder. You covet and cannot obtain, so you fight and quarrel.” James 4:1-2